package org.ff4j.store;

/*-
 * #%L
 * ff4j-store-ehcache
 * %%
 * Copyright (C) 2013 - 2024 FF4J
 * %%
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * #L%
 */

import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

import org.ff4j.core.Feature;
import org.ff4j.core.FeatureStore;
import org.ff4j.ehcache.FF4jEhCacheWrapper;
import org.ff4j.exception.FeatureAlreadyExistException;
import org.ff4j.exception.FeatureNotFoundException;
import org.ff4j.exception.GroupNotFoundException;
import org.ff4j.utils.Util;

import net.sf.ehcache.Cache;
import net.sf.ehcache.Element;
import net.sf.ehcache.config.Configuration;

/**
 * {@link FeatureStore} to persist data into
 *
 * @author <a href="mailto:cedrick.lunven@gmail.com">Cedrick LUNVEN</a>
 */
public class FeatureStoreEhCache extends AbstractFeatureStore {
  
    /** Wrap EHCACHE Manager. */
    private FF4jEhCacheWrapper wrapper;
    
    /**
     * Default Constructor.
     */
    public FeatureStoreEhCache() {
        wrapper = new FF4jEhCacheWrapper();
    }
    
    /**
     * Default Constructor.
     */
    public FeatureStoreEhCache(Configuration cacheConfig) {
        wrapper = new FF4jEhCacheWrapper(cacheConfig);
    }
    
    /**
     * Default Constructor.
     */
    public FeatureStoreEhCache(String xmlEhCacheConfig) {
        wrapper = new FF4jEhCacheWrapper(xmlEhCacheConfig);
    }
    
    
    /** {@inheritDoc} */
    @Override
    public boolean exist(String uid) {
        Util.assertParamHasLength(uid, "Feature identifier");
        return getCache().get(uid) != null;
    }
    
    /** {@inheritDoc} */
    @Override
    public Feature read(String uid) {
        if (!exist(uid)) {
            throw new FeatureNotFoundException(uid);
        }
       return (Feature) getCache().get(uid).getObjectValue();
    }
    
    /** {@inheritDoc} */
    @Override
    public void update(Feature fp) {
        if (fp == null) {
            throw new IllegalArgumentException("Feature cannot be null");
        }
        if (!exist(fp.getUid())) {
            throw new FeatureNotFoundException(fp.getUid());
        }
        getCache().put(new Element(fp.getUid(), fp));
    }
    
    /** {@inheritDoc} */
    @Override
    public void enable(String uid) {
        // Read from redis, feature not found if no present
        Feature f = read(uid);
        // Update within Object
        f.enable();
        // Serialization and update key, update TTL
        update(f);
    }

    /** {@inheritDoc} */
    @Override
    public void disable(String uid) {
        // Read from redis, feature not found if no present
        Feature f = read(uid);
        // Update within Object
        f.disable();
        // Serialization and update key, update TTL
        update(f);
    }

    /** {@inheritDoc} */
    @Override
    public void create(Feature fp) {
        if (fp == null) {
            throw new IllegalArgumentException("Feature cannot be null nor empty");
        }
        if (exist(fp.getUid())) {
            throw new FeatureAlreadyExistException(fp.getUid());
        }
        getCache().put(new Element(fp.getUid(), fp));
    }

    /** {@inheritDoc} */
    @Override
    public Map<String, Feature> readAll() {
        Map<String, Feature> myMap = new HashMap<String, Feature>();
        if (getCache().getKeys() != null) {
            for (Object key : getCache().getKeys()) {
                Element element = getCache().get(key);
                if (element != null) {
                    Feature f = (Feature) getCache().get(key).getObjectValue();
                    myMap.put((String) key, f);
                }
            }
        }
        return myMap;
    }

    /** {@inheritDoc} */
    @Override
    public void delete(String fpId) {
        if (!exist(fpId)) {
            throw new FeatureNotFoundException(fpId);
        }
        getCache().remove(fpId);
    }    

    /** {@inheritDoc} */
    @Override
    public void grantRoleOnFeature(String flipId, String roleName) {
        Util.assertParamHasLength(roleName, "roleName (#2)");
        // retrieve
        Feature f = read(flipId);
        // modify
        f.getPermissions().add(roleName);
        // persist modification
        update(f);
    }

    /** {@inheritDoc} */
    @Override
    public void removeRoleFromFeature(String flipId, String roleName) {
        Util.assertParamHasLength(roleName, "roleName (#2)");
        // retrieve
        Feature f = read(flipId);
        f.getPermissions().remove(roleName);
        // persist modification
        update(f);
    }
    
    /** {@inheritDoc} */
    @Override
    public Map<String, Feature> readGroup(String groupName) {
        Util.assertParamHasLength(groupName, "groupName");
        Map < String, Feature > features = readAll();
        Map < String, Feature > group = new HashMap<String, Feature>();
        for (Map.Entry<String,Feature> uid : features.entrySet()) {
            if (groupName.equals(uid.getValue().getGroup())) {
                group.put(uid.getKey(), uid.getValue());
            }
        }
        if (group.isEmpty()) {
            throw new GroupNotFoundException(groupName);
        }
        return group;
    }
    
    /** {@inheritDoc} */
    @Override
    public boolean existGroup(String groupName) {
        Util.assertParamHasLength(groupName, "groupName");
        Map < String, Feature > features = readAll();
        Map < String, Feature > group = new HashMap<String, Feature>();
        for (Map.Entry<String,Feature> uid : features.entrySet()) {
            if (groupName.equals(uid.getValue().getGroup())) {
                group.put(uid.getKey(), uid.getValue());
            }
        }
        return !group.isEmpty();
    }

    /** {@inheritDoc} */
    @Override
    public void enableGroup(String groupName) {
        Map < String, Feature > features = readGroup(groupName);
        for (Map.Entry<String,Feature> uid : features.entrySet()) {
            uid.getValue().enable();
            update(uid.getValue());
        }
    }

    /** {@inheritDoc} */
    @Override
    public void disableGroup(String groupName) {
        Map < String, Feature > features = readGroup(groupName);
        for (Map.Entry<String,Feature> uid : features.entrySet()) {
            uid.getValue().disable();
            update(uid.getValue());
        }
    }

    /** {@inheritDoc} */
    @Override
    public void addToGroup(String featureId, String groupName) {
        Util.assertParamHasLength(groupName, "groupName (#2)");
        // retrieve
        Feature f = read(featureId);
        f.setGroup(groupName);
        // persist modification
        update(f);
    }

    /** {@inheritDoc} */
    @Override
    public void removeFromGroup(String featureId, String groupName) {
        Util.assertParamHasLength(groupName, "groupName (#2)");
        if (!existGroup(groupName)) {
            throw new GroupNotFoundException(groupName);
        }
        // retrieve
        Feature f = read(featureId);
        f.setGroup(null);
        // persist modification
        update(f);
    }

    /** {@inheritDoc} */
    @Override
    public Set<String> readAllGroups() {
        Map < String, Feature > features = readAll();
        Set < String > groups = new HashSet<String>();
        for (Map.Entry<String,Feature> uid : features.entrySet()) {
            groups.add(uid.getValue().getGroup());
        }
        groups.remove(null);
        return groups;
    }

    /**
     * Retrieve cache. If not exist, created default cache
     * 
     * @return
     */
    private Cache getCache() {
        return wrapper.getCacheFeatures();
    }

    /** {@inheritDoc} */
    @Override
    public void clear() {
        wrapper.getCacheFeatures().removeAll();
    }    
}
